The present application relates generally to an improved data processing apparatus and method and more specifically to mechanisms for minimizing aggregate cooling and leakage power.
As computer and other electronic systems have increased performance over time, the power consumed to enable the performance has increased dramatically. Until recently, power management has mostly been an issue associated with the max temperatures components or subassemblies may experience. However, a system behavior that requires significant power during periods of high production, but requires very little power consumption during idle or low production periods, will tend to experience large variations in temperature depending upon the nature of the thermal cooling paths and the workload demands on the system. These temperature variations may cause failures due to mechanical stress and strain induced fatigue for structures that are composed of materials with varying coefficients of thermal expansion (CTE).
When a system is operating at a high temperature, more power is consumed, primarily due to increased thermally induced parasitic power, such as leakage power. In current systems, leakage power is controlled by setting a thermal threshold to approximately 70 degrees Celsius. When the temperature is exceeded, these systems turn to increasing fan speed, decreasing voltage, decreasing frequency, and/or decreasing workload, and when the temperature falls below the threshold, these systems decrease fan speed, increase voltage, increase frequency, and/or increasing workload. Such changes may lead to failures due to mechanical stress and strain induced fatigue for structures as previously described.